Capsule for beverage preparation with integrally formed sealing member

ABSTRACT

The invention relates to a capsule (10) designed for preparing a beverage upon injection of liquid into the capsule by means of a beverage preparation machine, the capsule (10) comprising a cup-shaped base body (1) for holding beverage preparation ingredients and a flange-like rim (2) with a sealing member (3) comprising an inner and an outer series (4, 5) of arc-shaped protrusions (4a, 5a), wherein the base-body (1), the flange-like rim (2) and the sealing member (3) are made integrally from metallic material such as aluminum, wherein the inner and outer series (4, 5) of the sealing member (3) are concentrically arranged on a surface (2a) of the flange-like rim (2) such as to form an annular space (6) there-between for receiving a sealing surface (21a) of a capsule engagement member (21) of the beverage preparation machine (20), wherein the respective arc-shaped protrusions (4a, 5a) of the inner and outer series (4, 5) are continuous protrusions with circumferentially extending gaps (4b, 5b) formed there-between, and wherein the respective arc-shaped protrusions (4a, 5a) of the inner and outer series (4, 5) are arranged such as to circumferentially overlap outside the gaps (4b, 5b) of the inner and outer series (4, 5) in side view of the capsule.

FIELD OF THE INVENTION

The present invention relates to a capsule designed for preparation of afood product such as a beverage with enhanced sealing means. Inparticular, the invention relates to a capsule having a body with anintegrally formed sealing member made from metallic material such asaluminum.

BACKGROUND AND OBJECT OF THE INVENTION

Capsules for preparation of a food product such as a beverage are widelyknown in the market. An example of such capsule that is intended forbeing used with a beverage preparation machine is described in EP 0 512468 A1. For beverage preparation in a dedicated beverage preparationmachine, the capsule is inserted to the machine and ingredientscontained in the capsule are made to interact with liquid provided tothe capsule in order to form a desired beverage that is then made toleave the capsule. Thereby, the capsule is opened under the effect ofrising pressure within the capsule, which urges an outlet face of thecapsule against opening means such as raised elements provided on asupporting part of the beverage preparation machine. Sealing of thecapsule during the beverage preparation process is obtained by an outerportion of a flange-like rim of the capsule which is contacted along acircumferential contact line by a suitably shaped engagement member ofthe beverage preparation machine.

In order to enhance sealing between the capsule and an engagement memberof the beverage preparation machine, capsules have been developed inwhich a dedicated sealing member is applied and wherein the sealingmember is of different material than the capsule body. EP1654966, EP 1849 715 and EP2151313 for example relate to such a capsule in which asealing member of rubber elastic material is applied to the capsule. Thesealing member may be applied onto the capsule body by means of liquiddepositing and hardening, gluing or by crimping a portion of the capsulebody and/or the flange-like rim of the capsule onto the sealing member.

A disadvantage of these capsules is a more complex manufacturing processin which the capsule and the sealing member are manufactured inindividual manufacturing steps and then assembled. The solution is alsocostly to produce both in terms of material cost and production cost.Therefore, a solution is sought-after which enables a facilitatedmanufacturing process while at the same time providing enhanced sealingproperties of the flange-like rim of the capsule.

Capsules are also known, which comprise an integrally formed sealingmember, i.e. a sealing member made from the same material as the capsulebody respectively the flange-like rim of the capsule. EP 2 303 077 B1,EP 2 387 922 B1 and EP 2 814 328 B1 for example relate to a capsulecomprising a sealing member formed of a plurality of concentric annularprotrusions integrally formed with the flange-like rim.

WO2014/012783, WO2014/184652, WO2016/186489, WO2016/186495 andWO2016/186496 also disclose capsules for beverage preparation and whichcomprise a flange-like rim portion with an integrally formed annularsealing member.

WO2016207845 relates to a plastic capsule comprising a flange-like rimwith a single annular sealing ring that is enclosed by inner and outercentering projections, the centering projections comprising a multitudeof arc-shaped elements separated circumferentially by gaps and which aredesigned to provide a better centering of the sealing ring with respectto a circumferential sealing edge of a beverage preparation machine.

These known capsules however suffer the disadvantage that due to thecircumferentially arranged protrusions of the sealing member, tensionsmay occur during forming of the protrusions in the manufacturingprocess, which in turn lead to defects in the sealing member and/or theflange-like rim and which negatively affect the sealing properties ofthe sealing member. This particularly applies for metal capsules, e.g.made from aluminum. Thereby, defects such as stress cracking, wrinklingand other surface defects may occur during the deep drawing process ofaluminum when forming the capsule. In addition, the circumferentiallyarranged sealing protrusions may lead to a less tolerant sealingadjustment with concentricity problems.

It is therefore an object of the present invention to provide animproved capsule which overcomes the disadvantages of the prior artsolutions. This object is solved by the independent claims. Thedependent claims define further preferred embodiments of the invention.

SUMMARY OF THE INVENTION

The invention relates to a capsule designed for preparing a beverageupon injection of liquid into the capsule by means of a beveragepreparation machine, the capsule comprising a cup-shaped base body forholding beverage preparation ingredients and a flange-like rim with asealing member comprising an inner and an outer series of arc-shapedprotrusions, wherein the base-body, the flange-like rim and the sealingmember are made integrally from metallic material such as aluminum,wherein the inner and outer series of the sealing member areconcentrically arranged on a surface of the flange-like rim such as toform an annular space there-between for receiving a sealing surface of acapsule engagement member of the beverage preparation machine, whereinthe respective arc-shaped protrusions of the inner and outer series arecontinuous protrusions with circumferentially extending gaps, andwherein the respective arc-shaped protrusions of the inner and outerseries are arranged such as to circumferentially overlap outside thecircumferentially extending gaps in side view of the capsule.

The capsule according to the invention enables a reliable and tolerantsealing structure made from a single integral piece and thus by omittingany additional material such as rubber. The capsule may thus be formedin a facilitated manufacturing process at reduced costs, while at thesame time providing an enhanced sealing member without any materialdefects such as cracks, wrinkling and surface defects that could affectthe capsule quality and tightness and as well the extraction process.

The term “overlap” in the sense of the present application relates tothe respective arc-shaped protrusions of the inner and outer series ofprotrusions being arranged such that the respective protrusions are atleast partially covering each other in side view (see direction SV inFIG. 4). In particular, when seen in side view, the respectivearc-shaped protrusions of the outer series of protrusions at leastpartially overlaps respectively covers the respective arc-shapedprotrusion arranged of the inner series of protrusions such as to coverany gaps formed between the arc-shaped protrusions of the inner series.In top view onto the flange-like rim, the respective arc-shapedprotrusions are overlapping at least partially in radial direction.

The flange-like rim is preferably an essentially planar collar thatextends from an open end of the cup-shaped base body essentiallyperpendicular to outer lateral side walls of the base body and/or to arotational axis of the capsule. The inner and outer series of arc-shapedprotrusions are arranged distant from the cup-shaped base body and fromthe outer periphery of the flange-like rim.

The respective protrusions of the sealing member are preferablyintegrally formed in the otherwise essentially planar flange-like rim.The protrusions formed in the flange-like rim preferably comprise amaterial thickness essentially corresponding to the rest of theflange-like rim.

The protrusions in the flange-like rim are preferably made by adeep-drawing process. In a preferred embodiment, the capsule body, theflange-like rim and the sealing member are manufactured in a singledeep-drawing process. The capsule may e.g. be produced by deep-drawingan initially flat metal sheet.

The capsule is preferably made from a single sheet of metal such asaluminum.

The respective arc-shaped protrusions of the inner and outer series ofthe sealing member are arranged on the same surface of the flange-likerim. The surface is directed towards the cup-shaped base body of thecapsule. On a surface of the flange-like rim opposite thereto, a closingmembrane may be connected to the capsule base body.

The respective arc-shaped protrusions of the inner and outer series ofthe sealing member are preferably continuous protrusions with gapsformed between the respective protrusions of each series. The gaps arethus annular gaps which extend between respective adjacent arc-shapedprotrusions of the inner and outer series.

The inner and outer series of the arc-shaped protrusions preferably eachcomprise at least two, preferably at least three or four arc-shapedprotrusions. The inner and outer series may as well each comprise amultitude of arc-shaped protrusions.

The overlap between the respective arc-shaped protrusions of the innerand outer series of protrusions preferably equals at least 10%,preferably at least 20% but less than 50% of an arc length L of therespective overlapping protrusions. Thereby, the arc length L refers tothe minimum arc length of the respective overlapping arc-shapedprotrusions of the inner and outer series of protrusions. The arc lengthof each protrusion along the circumference of the flange-like rimdepends on the total number of protrusions for both the inner and outerseries of protrusions. The higher the number, the shorter the respectivearc length.

The overlap angular length between the respective arc-shaped protrusionsis between 5° and 90°, preferably between 10° and 70°, most preferablybetween 20° and 60°.

In a preferred embodiment, the respective arc-shaped protrusions of theinner and outer series are radially arranged equidistant to each otherabout the circumference of the base-body such as to form constantcircumferentially extending gaps between the respective protrusions.

The annular space between the inner and outer series of arc-shapedprotrusions is designed for receiving a preferably annular sealingsurface of a capsule engagement member of the beverage preparationmachine. The engagement member is preferably an essentially bell-shapedengagement member respectively a so-called capsule cage designed tohouse the cup-shaped base body of the capsule. The sealing surface ofthe engagement member may be a flat or rounded end surface of theengagement member.

In a preferred mode, the sealing surface of the engagement member isarranged for engaging the protrusions of the inner series of arc-shapedprotrusions and the protrusions of the outer series of arc-shapedprotrusions. The engagement of the sealing surface of the engagementmember may be such that it may deform at least partially theprotrusions. The engagement of the sealing surface of the engagementmember may be such that it provides at least substantially radiallyoriented sealing forces with the protrusions.

The annular space between the inner and outer series of arc-shapedprotrusions is preferably void of any protrusion. A bottom portion ofthe annular space is preferably a flat annular portion. The bottomportion of the annular space preferably corresponds to an upper surfaceof the flange-like rim portion.

The inner and outer series of arc-shaped protrusions are arranged at aradial distance d of between 0.6 to 1.2 mm, more preferably between 0.8and 1.0 mm for forming the annular space there-between. The radialdistance d thus relates to a thickness of the annular space forreceiving the sealing surface of the capsule engagement member. Thedistance d between the respective arc-shaped protrusions is preferablychosen such as to be equal to or less than a radial width D of theannular sealing surface.

In a preferred embodiment, the radial distance d is chosen to be atleast 1-2%, preferably at least 2-5% less than the radial width of theannular sealing surface of the engagement member of the beveragepreparation machine.

In a preferred embodiment, the respective protrusions of the inner andouter series comprise essentially the same dimensions in sectional sideview. The respective protrusions of the inner and outer series maycomprise the same height and/or width.

However, the respective protrusions may be of different height and/orwidth. For example, the protrusions of the outer series may be ofsmaller height than the protrusions of the inner series or vice versa.For example, the protrusions of the outer series may be of smaller widththan the protrusions of the inner series or vice versa.

The protrusions in each inner or outer series may be of different heightand/or width.

The respective protrusions of the inner and outer series preferablycomprise a base width BW of between 0.3 and 1.3 mm, more preferablybetween 0.5 and 1.0 mm and/or a height H of between 0.8 and 1.7 mm, morepreferably between 1 and 1.5 mm.

The respective protrusions preferably comprise in sectional side view alower base portion B with two opposing preferably linear wall sectionsand an upper portion A with two opposing preferably rounded wallsections.

The two opposing rounded wall sections of the upper portion A arepreferably joined by a rounded tip portion C.

The two opposing linear wall sections are preferably arranged toconverge towards the upper portion A of the respective protrusions. Thetwo opposing linear wall sections are preferably arranged at an angle ofinclination of between 3 to 12°, more preferably of between 5 to 10°with respect to the normal of the flange-like rim and/or with respect toa rotational axis of the capsule.

The two opposing rounded wall sections of the upper portion A preferablycomprise a radius R1 of between 0.5 to 5.5, more preferably between 1and 5 mm.

The rounded tip portion C preferably comprise a radius R2 of between 0.2and 2.3 mm, more preferably between 0.5 and 2 mm.

The two opposing wall sections of the lower portion B may be notstrictly linear but slightly convex. For example, the two opposing wallsections A and B may form together continuously convex wall sections ofincreasing curvature in direction to the tip portion C.

The capsule preferably further comprises a closing membrane connected tothe base body and/or the flange-like rim of the capsule. The closingmembrane is preferably connected to a surface of the flange-like rimopposite to the surface at which the inner and outer series ofarc-shaped protrusions are arranged. The closing membrane may beconnected to the flange-like rim by means of an adhesive and/or weldingtechnique. The closing membrane is preferably a closed membrane, i.e.void of any perforations. The closing membrane may however as wellcomprise pre-formed perforations therein. The closing membrane ispreferably an aluminum foil. The foil is preferably sealed to theflange-like rim such as to form a seal hermetical to gas with thecapsule base body for preserving freshness of the ingredients containedin the cartridge.

In a further aspect, the invention relates to a system comprising acapsule as described above and a beverage preparation machine designedto provide heated and/or pressurized liquid into the capsule forpreparing a beverage upon interaction of the liquid with ingredientsheld within the capsule.

The beverage preparation machine preferably comprises a pump, heatingand/or cooling means, a liquid supply such as a water tank and/or abeverage brewing chamber for selectively receiving a capsule in order toprepare a beverage therefrom.

The beverage preparation machine preferably comprises a capsuleengagement member, e.g. as part of the brewing chamber, which isdesigned to house a capsule and in particular the capsule base body whenthe capsule is provided into the machine. The engagement membercomprises an annular sealing surface designed to interact with thesealing member of the capsule in order to enable an effective sealing ofthe capsule during the beverage preparation process. As mentionedearlier, the sealing surface of the engagement member may be arrangedfor engaging the protrusions of the inner series of arc-shapedprotrusions and the protrusions of the outer series of arc-shapedprotrusions. The engagement of the sealing surface of the engagementmember may be such that it may deform at least partially theprotrusions. The engagement of the sealing surface of the engagementmember may be such that it provides at least substantially radiallyoriented sealing forces with the protrusions.

The beverage preparation machine preferably further comprisesperforation means such as injection blades or the like, which aredesigned to perforate an inlet face of the capsule, in particularsituated at a closed end of the capsule base body, and to inject liquidinto the capsule interior.

The beverage preparation machine preferably further comprises a capsulesupport designed to hold the flange-like rim of the capsule at a sideopposite to a side at which the engagement member of the machine engagesthe sealing member of the capsule. The capsule support preferablycomprises opening means such as e.g. truncated pyramid-like elementsagainst which a closing membrane of the capsule may be urged duringpressure rise within the capsule such as to open the closing member e.g.by of tearing or rupturing.

The capsule according to the present invention is preferably rotationalsymmetric, i.e. symmetric along its vertical axis.

The thickness t of the base body of the capsule preferably lies between0.3 and 1.7 mm, more preferably between 0.7 and 1.3 mm. The thickness t1of the closing membrane preferably lies between 60 and 100 microns(including the embossed structure and lacquer(s) on surface).

The beverage preparation ingredients provided in the capsule arepreferably chosen from the group consisting of roasted ground coffee,tea, instant coffee, a mixture of roasted ground coffee and instantcoffee, a syrup concentrate, a fruit extract concentrate, a chocolateproduct, a milk-based product or any other dehydrated edible substance,such as dehydrated stock. The liquid to be used for beverage preparationis preferably water of any temperature.

The invention further relates to a cup-shaped base body of a capsule forpreparation of a food product with an enhanced integrally formed sealingmember.

BRIEF DESCRIPTION OF THE FIGURES

Further features, advantages and objects of the present invention willbecome apparent for a skilled person when reading the following detaileddescription of embodiments of the present invention, when taken inconjunction with the figures of the enclosed drawings.

FIG. 1a is a perspective side view of a preferred embodiment of acapsule according to the invention.

FIG. 1b is a top view of the capsule according to FIG. 1 a.

FIG. 2 is a schematic top view onto a preferred embodiment of a capsuleaccording to the invention.

FIG. 3 is a cross sectional side view of a protrusion of the sealingmember according to the invention.

FIG. 4 is a sectional side view in direction S of FIG. 2 of a preferredembodiment of the sealing member according to the invention and anengagement member of a beverage preparation machine before engaging witheach other.

FIG. 5 is a sectional side view in direction V of FIG. 2 of a preferredembodiment of the sealing member according to the invention and anengagement member of a beverage preparation machine before engaging witheach other.

FIG. 6 is a sectional side view in direction T of FIG. 2 of a preferredembodiment of the sealing member according to the invention and anengagement member of a beverage preparation machine before engaging witheach other

DETAILED DESCRIPTION OF THE FIGURES

FIGS. 1a and 1b relate to a preferred embodiment of a capsule 10according to the invention. The capsule 10 comprises a cup-shaped basebody 1. The base body 1 comprises a closed end 10 a and an open end 10b. The closed end 10 a may serve as an injection face during a beveragepreparation process, which may be opened by a dedicated injection memberof a beverage preparation machine 20.

The capsule 10 further comprises a flange-like rim 2 which is preferablyarranged at the open end 10 b of the capsule 10. The flange-like rim 2may extend 1 radially outwardly from lateral sidewalls of the cup-shapedbase body 1. The flange-like rim 2 is preferably arranged transversallyto a rotational axis Y of the capsule 10.

At the open end 10 b of the capsule base body 1 a closing membrane 9 maybe arranged. The closing membrane 9 is preferably connected to theflange-like rim 2 (see FIG. 4). The closing membrane 9 is preferablyconnected to at least one lower annular surface 2 b of the flange-likerim 2, which surface 2 b is directed away from the capsule base body 1.

The cup-shaped base body 1 preferably encloses beverage ingredientssuitably for preparing a liquid comestible upon interaction with liquidinjected into the capsule 10. The ingredients are preferably enclosed bythe cup-shaped base body 1 and the closing membrane 9. The beverageingredients may be roasted ground coffee or other kinds of ingredientsas previously described.

The flange-like rim 2 comprises an integrally formed sealing member 3which is arranged at an upper annular surface 2 a of the flange-likerim. The annular surface 2 a is arranged opposite to the surface 2 b towhich the closing membrane 9 is preferably connected. The annularsurface 2 a is thus facing away from the open end 10 b of the capsule.

The sealing member 3 comprises an inner and an outer series ofarc-shaped protrusions 4,5, which are concentrically arranged on thesurface 2 a of the flange-like rim 2. The inner and outer series 4,5 ofarc-shaped protrusion are integrally formed with the flange-like rim 2.This means that they are formed of same material as the flange-like rimand from the flange-like rim such as (and are not add-on parts) toprotrude from the surface 2 a.

The inner and an outer series of arc-shaped protrusions 4,5 are arrangedto form an annular space 6 there-between for receiving a sealing surface21 a of a capsule engagement member of the beverage preparation machine20 (see FIG. 4). Therefore, a radial distance d between the inner andouter series 4,5, is preferably chosen such as the protrusions suitablyinteract in sealing engagement with the dedicated sealing surface 21 aof the engagement member 21. More particularly, in the overlap region(FIG. 4), the dedicated sealing surface actually splits into a sealingsurface portion 21 aa which engages the protrusions 4 b of the outerseries and a sealing surface portion 21 ab which engages the protrusions4 a of the inner series. The radial distance d is preferably between 0.6to 1.2 mm, more preferably between 0.8 and 1.0 mm. The annular space 6between the inner and outer series 4,5 is preferably void of anyprotrusion. The annular space 6 thus preferably comprises an essentiallyflat bottom surface 2 d which interconnects adjacent arc-shapedprotrusions of the inner and outer series 4,5.

The cup-shaped base body 1, the flange-like rim 2 and the sealing member3 are integrally formed, i.e. by one single piece made from the samematerial. Accordingly, the cup-shaped base body 1, the flange-like rim 2and the sealing member 3 can be manufactured from the same material by aforming process. In particular, the base body 1, the flange-like rim 2and the integrally formed sealing member 3 can be formed in adeep-drawing process. The deep drawing process may require more than onedeep drawing step to properly form from a flat piece of material thebody of the capsule and the sealing member.

The base body 1, the flange-like rim 2 and the sealing member 3 areformed of one piece made of metal, preferably of aluminum, mostpreferably an aluminium alloy.

The inner and an outer series of arc-shaped protrusions 4,5 arepreferably arranged on the surface 2 a distant from an outercircumferential edge or outer end 2 c of the flange-like rim 2. Theinner and outer series 4,5 are further arranged distant from thecup-shaped base body 1 of the capsule 1. The inner and outer series ofarc-shaped protrusions 4,5, is preferably arranged at an annular portionof the surface 2 a of the flange-like rim 2 which is nearer to thecup-shaped body 1 than to the outer end 2 c. The relative position ofthe inner and outer series of arc-shaped protrusions on the flange-likerim naturally depends on the matching position of the sealing surfacesdetermined by the dimensions of the engaging member.

The inner and outer series of arc-shaped protrusions 4,5 each compriseindividual arc-shaped protrusions 4 a,5 a arranged at a predefinedradius about a rotational axis Y of the capsule 10. The inner and outerseries of the arc-shaped protrusions 4,5 each preferably comprise atleast two, more preferably at least three, four, five or six arc-shapedprotrusions 4 a,5 a. The respective arc-shaped protrusions 4 a,5 a ofthe inner and outer series 4,5 are preferably continuous protrusionswith gaps 4 b,5 b formed there-between.

The respective arc-shaped protrusions 4 a,5 a of the inner and outerseries 4,5 are arranged such as to overlap in side view of the capsule.The respective arc-shaped protrusions 5 a of the outer series 5 thusoverlap with circumferentially extending gaps 4 b formed between therespective arc-shaped protrusions 4 a of the inner series 4 in side viewof the capsule and vice versa. The overlap between the respectivearc-shaped protrusions 4 a,5 a preferably equals at least 20 to 25%,more preferably 30 to 35% of an arc length L of the respectiveoverlapping protrusions 4 a,5 a. The respective arc-shaped protrusions 4a,5 a of the inner and outer series 4,5 are thus arranged at differentangles along the 360° circumference of the flange-like rim 2 when seenin top view.

The respective arc-shaped protrusions 4 a,5 a of the inner and outerseries 4,5 may be arranged circumferentially at equidistance to eachother about the circumference of the base-body such as to form constantcircumferentially extending gaps 4 b,5 b between the respectiveprotrusions 4 a,5 a in the respective series 4,5.

FIG. 2 relates to a schematic top view onto a capsule 10 according tothe invention in which the respective radii of the capsule 10 areindicated. As shown in FIG. 2, the capsule base body 1 and theflange-like rim merge at a circumferential edge indicated as r1 andwhich radius preferably lies between 12 and 18 mm, and most preferablyis 15 mm. The outer radius r6 of the flange-like rim 2 at the outer end2 c preferably lies between 18 and 20 mm, and most preferably is 18.5mm.

The difference between r2 and r3 corresponds to a radial extension ofthe arc-shaped protrusions 4 a and the respective intermediate gaps 4 bof the inner series of protrusions 4 and preferably lies between 0.3 and1.3 mm, more preferably between 0.5 and 1.0 mm.

The difference between r4 and r5 corresponds to a radial extension ofthe arc-shaped protrusions 5 a and the respective intermediate gaps 5 bof the outer series of protrusions 5 and preferably lies between 0.3 and1.3 mm, more preferably between 0.5 and 1.0 mm.

The difference between r3 and r4 corresponds to a radial extensionrespectively radial distance d of the arc-shaped protrusions 4 a,5 a asindicated above. A particularly preferred value for the radial distanced is between 0.7 and 1.1 mm, and most preferably is 0.9 mm.

The overlap angular length A between the respective arc-shapedprotrusions is between 5° and 90°, preferably between 10° and 70°, mostpreferably between 20° and 60°.

FIG. 3 relates to a cross section side view of an exemplary embodimentof an arc-shaped protrusion 4 a,5 a. The arc-shaped protrusions 4 a,5 apreferably comprise essentially the same dimensions in sectional sideview. However, the arc-shaped protrusions 4 a, 5 a could also havedifferent dimensions in sectional side view.

The respective protrusions 4 a,5 a preferably comprise a lower baseportion B with two opposing linear wall sections b1 and b2 and an upperportion A with two opposing rounded wall sections a1 and a2. The twoopposing rounded wall sections a1 and a2 of the upper portion A arepreferably joined by a rounded tip portion C.

The two opposing linear wall sections b1,b2 are preferably arranged toapproach towards the upper portion A of the respective protrusions 4 a,5a. The two opposing linear wall sections b1,b2 are preferably arrangedat an angle α of inclination of between 3 to 12°, more preferably ofbetween 5 to 10° with respect to the normal N of the flange-like rim 2and/or with respect to a rotational axis Y of the capsule 10.

The two opposing rounded wall sections a1,a2 of the upper portion Apreferably comprise a radius R1 of between 0.5 to 5.5, more preferablybetween 1 and 5 mm. The rounded tip portion C preferably comprise aradius R2 of between 0.2 and 2.3 mm, more preferably between 0.5 and 2mm.

A base width BW of the respective protrusions 4 a,5 a preferably liesbetween 0.3 and 1.3 mm, more preferably between 0.5 and 1.0 mm. Theheight H preferably lies between 0.8 and 1.7 mm, more preferably between1 and 1.5 mm.

The base portion B preferably extends to a height h1 of between between⅓ to ½ of overall height H. Correspondingly, upper portion A may extendto a height h2 of between ⅔ to ½ of overall height H.

The projections 4 a, 5 a may comprise free ends 7 a, 7 b ofprogressively reducing dimensions to ensure a smoother transition withthe surface 2 a of the flange-like rim. The width r3-r2, r5-r4 andheight H at these free ends 7 a, 7 b preferably diminish progressivelytowards circumferentially extending gaps 4 b, 5 b. In particular, theshape of these ends 7 a, 7 b may be slightly triangular or rounded whenviewed from the top in direction of the flange-like rim as illustratedin FIG. 2. As a result, the forming of the projections is facilitatedwith lower risk of cracks or wrinkles.

FIG. 4 is a sectional side view of a preferred embodiment of the sealingmember 3 of the capsule 10 and an engagement member 21 of a beveragepreparation machine 20 before engaging with each other.

As shown in FIG. 4, the respective protrusions 4 a,5 a of the sealingmember 3 are preferably hollow. Accordingly, the protrusions 4 a,5 a arenot filled with material of the flange-like rim 2, but are formed by acontour of wall thickness t2. The respective protrusions 4 a,5 a thuspreferably form a hollow body that is open to the lower surface 2 b ofthe flange-like rim 2.

Due to the drawing process, the wall thickness t1 of the flange-like rim2 may generally be slightly larger than the wall thickness t2 of theprotrusions 4 a,5 a for the same reason, the wall thickness t1, t2 maygenerally be larger than the wall thickness t_(b) of the base body 2 ofthe capsule.

The engagement member 21 of a dedicated beverage preparation machine 20is preferably an essentially hollow bell-shaped engagement member forreceiving the capsule base body 1 therein. When the capsule 10 is placedinto the beverage preparation machine 20, the engagement member 21 willbe lowered onto the capsule 10 by means of a dedicated closing force Fas indicated in FIG. 4. The sealing surface 21 a of the engagementmember 21 may be an annular lower surface with rounded inner and outercircumferential edges. The front surface 21 a comprises a radialthickness D which preferably lies between 0.8 and 1.2, more preferablybetween 0.9 and 1.1 mm.

The annular space 6 between the protrusions 4 a,5 a of the inner andouter series 4,5 of the sealing member 3 is designed for receiving thesealing surface 21 a of the capsule engagement member 21 of the beveragepreparation machine 20. The annular space 6 comprises a preferably flatannular bottom surface 6 a which interconnects the neighboringprotrusions 4 a,5 a. The annular bottom surface 6 a extends to a radialdistance respectively thickness d as described above. The distance d ispreferably chosen such as to be equal to or slightly smaller than anannular radial thickness D of the sealing surface 21 a of the engagementmember 21. In a preferred embodiment, thickness d is chosen to bebetween 0.1 and 0.5, more preferably between 0.2 to 0.3 mm smaller thanthe annular radial thickness D of the sealing surface 21 a.

The annular space 6 preferably widens from the bottom surface 6 atowards the tip portions C of the neighboring protrusions 4 a,5 a.Thereby, the respective upper ends of the base portions B of neighboringprotrusions 4 a,5 a are preferably distanced by a radial distance dlthat is larger than the distance d at the bottom surface 6 a. Thedistance dl is preferably chosen to be 0.2 to 0.3 mm larger than theradial thickness D of the sealing surface 21 a of the engagement member21.

When the engagement member 21 is lowered from the position shown in FIG.4 onto the sealing member 3 by closing force F, the annular sealingsurface 21 a will engage in the annular space 6, thereby providing afluid tight engagement between the sealing surface 21 a and theneighboring arc-shaped protrusions 4 a,5 a of the sealing member 3.

In the circumferentially overlapping regions of the protrusions 4 a, 5 b(FIG. 4), the engagement of the sealing surface 21 may be completed bothby the engagement of the outer sealing surface portion 21 aa with thewall of the protrusions 5 a of the outer series and by the engagement ofthe inner sealing surface portion 21 ab with the wall of the protrusions4 a of the inner series. Additionally, the rounded tip portion C may beengaged by a correspondingly formed annular receiving groove E of theengagement member 21. Accordingly, an effective sealing engagementbetween the sealing member 3 and the enclosing member 21 of the beveragepreparation machine is obtained.

As illustrated in FIGS. 5 and 6 respectively, outside thecircumferentially overlapping regions of the protrusions, the sealingengagement of the sealing surface of the engagement member 21 may belimited to one of the sealing surface portions 21 ab or 21 aarespectively with the projections 4 a of the inner series (FIG. 5) orthe projections 5 a of the outer series (FIG. 6) respectively. As theengagement member is moved towards the flange-like rim by pressureeffect during closing and/or extraction, the sealing surface portions 21aa, 21 ab may deform the projections and increase the contact surfacearea with the projections accordingly.

In particular, as shown in FIG. 5, the radius rei of the position of thesealing surface portion 21 ab of the engaging member 21 suitable toengage the projections 4 a of the inner series is preferably chosensmaller than the outer radius r3 of protrusions 4. As shown in FIG. 6,the radius ree of the position of the sealing surface portion 21 aa ofthe engaging member 21 suitable to engage the projections 5 a of theinner series is preferably chosen larger than the radius r4 of theradial extension of the arc-shaped protrusions 5 a. As a result, asealing pressure is exerted about the whole circumference of the sealingsurface 21 a of the engagement member by the sealing member 3 therebyensuring a sealing continuity.

The closing membrane 9 is preferably sealed on the annular bottomsurfaces 2 d and the outer annular surface 2 b. Preferably, the annularbottom surface 2 d between the inner and outer series 4,5 is notelevated or lowered relative to the outer annular surface 2 b and/or theinner annular bottom surface 2 d. preferably, the annular bottomsurfaces 2 d and the outer annular surface 2 b are preferablysubstantially aligned.

As also shown in FIG. 4, the closing membrane 9 is connected to anannular outer portion of the surface 2 b of the flange-like rim. Theclosing membrane 9 may additionally be connected to intermediate annularsurfaces 2 d arranged between the outer annular surface 2 b and thecapsule base body 1. The closing membrane 9 is preferably an aluminumfoil sealed to the flange-like rim 2.

At an outer peripheral edge 2 c, the flange-like rim 2 may comprise arollover edge 11 known in the present technical field.

1-21. (canceled)
 22. A capsule designed for preparing a beverage uponinjection of liquid into the capsule by use of a beverage preparationmachine, the capsule comprising a cup-shaped base body for holdingbeverage preparation ingredients and a flange-like rim with a sealingmember comprising an inner and an outer series of arc-shapedprotrusions, wherein the base-body, the flange-like rim and the sealingmember are made integrally from metallic material such as aluminum,wherein the inner and outer series of the sealing member areconcentrically arranged on a surface of the flange-like rim such as toform an annular space there-between for receiving a sealing surface of acapsule engagement member of the beverage preparation machine, therespective arc-shaped protrusions of the inner and outer series arecontinuous protrusions with circumferentially extending gaps formedthere-between, and the respective arc-shaped protrusions of the innerand outer series are arranged such as to circumferentially overlapoutside the circumferentially extending gaps of the inner and outerseries in side view of the capsule.
 23. The capsule of claim 22, whereinthe inner and outer series of the arc-shaped protrusions each compriseat least two arc-shaped protrusions.
 24. The capsule of claim 22,wherein the overlap between the respective arc-shaped protrusions equalsat least 20 to 25% of an arc length of the respective overlappingprotrusions.
 25. The capsule of any of the preceding claim 22, whereinthe overlap angular length between the respective arc-shaped protrusionsis between 5° and 90°.
 26. The capsule of claim 22, wherein therespective arc-shaped protrusions of the inner and outer series arearranged equidistant to each other about the circumference of thebase-body such as to form constant circumferentially extending gapsbetween the respective protrusions.
 27. The capsule of claim 22, whereinthe inner and outer series of arc-shaped protrusions are arrangeddistant from the cup-shaped base body and an outer periphery of theflange-like rim.
 28. The capsule of claim 22, wherein the annular spacebetween the inner and outer series of arc-shaped protrusions is void ofany protrusion.
 29. The capsule of claim 22, wherein the inner and outerseries of arc-shaped protrusions are arranged at a radial distance ofbetween 0.6 to 1.2 mm.
 30. The capsule of claim 22, wherein therespective protrusions of the inner and outer series compriseessentially the same dimensions in sectional side view.
 31. The capsuleof claim 22, wherein the respective protrusions of the inner and outerseries comprise a base width of between 0.3 and 1.3 mm and a height ofbetween 0.8 and 1.7 mm.
 32. The capsule of claim 22, wherein therespective protrusions comprise in sectional side view a lower baseportion with two opposing linear wall sections and an upper portion withtwo opposing rounded wall sections.
 33. The capsule of claim 32, whereinthe two opposing rounded wall sections of the upper portion are joinedby a rounded tip portion.
 34. The capsule of claim 32, wherein the twoopposing linear wall sections are arranged to converge towards the upperportion of the respective protrusions.
 35. The capsule of claim 22,wherein the capsule body, the flange-like rim and the sealing member areproduced by deep drawing an initially flat metal sheet.
 36. The capsuleof claim 22, wherein the capsule is made from aluminum.
 37. The capsuleof claim 22, wherein the capsule further comprises a closing membraneconnected to the base body and/or the flange-like rim of the capsule.38. The capsule according to claim 37, wherein the closing membrane isconnected to a surface of the flange-like rim opposite to the surface atwhich the inner and outer series of arc-shaped protrusions are arranged.39. The capsule according to claim 37, wherein the closing membrane isan aluminum foil sealed to the flange-like rim.
 40. A system comprisinga capsule designed for preparing a beverage upon injection of liquidinto the capsule by use of a beverage preparation machine, the capsulecomprising a cup-shaped base body for holding beverage preparationingredients and a flange-like rim with a sealing member comprising aninner and an outer series of arc-shaped protrusions, wherein thebase-body, the flange-like rim and the sealing member are madeintegrally from metallic material such as aluminum, wherein the innerand outer series of the sealing member are concentrically arranged on asurface of the flange-like rim such as to form an annular spacethere-between for receiving a sealing surface of a capsule engagementmember of the beverage preparation machine, the respective arc-shapedprotrusions of the inner and outer series are continuous protrusionswith circumferentially extending gaps formed there-between, and therespective arc-shaped protrusions of the inner and outer series arearranged such as to circumferentially overlap outside thecircumferentially extending gaps of the inner and outer series in sideview of the capsule and a beverage preparation machine designed toprovide heated and/or pressurized liquid into the capsule for preparinga beverage upon interaction of the liquid with ingredients held withinthe capsule.
 41. A cup-shaped base body of a capsule for holdingbeverage preparation ingredients and a flange-like rim with a sealingmember comprising an inner and an outer series of arc-shapedprotrusions, wherein the base-body, the flange-like rim and the sealingmember are made integrally from metallic material such as aluminum,wherein the inner and outer series of the sealing member areconcentrically arranged on a surface of the flange-like rim such as toform an annular space there-between for receiving a sealing surface of acapsule engagement member of the beverage preparation machine, whereinthe respective arc-shaped protrusions of the inner and outer series arecontinuous protrusions with circumferentially extending gaps formedthere-between, and wherein the respective arc-shaped protrusions of theinner and outer series are arranged such as to circumferentially overlapoutside the circumferentially extending gaps of the inner and outerseries in side view of the capsule.